In wireless systems, when a plurality of wireless terminals transmit data using the same radio resources (frequency and time), mutual data may collide, interference may occur, and thus reception of data on reception sides may fail in some cases. For this reason, when there are a plurality of wireless terminals using the same frequency, it is desirable to provide a mechanism enabling one wireless terminal to monopolize the frequency at a certain time slot as much as possible and transmit data so that the data does not collide.
As one of the technologies for providing such a mechanism, there is a technology for avoiding collision using carrier sense. According to the present technology, a wireless terminal enters a reception mode before data transmission to measure reception power at a frequency channel (hereinafter also referred to as a channel) to be used. Then, the wireless terminal avoids data collision by determining a threshold for the measured reception power and suppressing transmission until the wireless terminal confirms empty radio resources. Hereinafter, this threshold is also referred to as a carrier sense level. A technology for setting an appropriate carrier sense level in order to suppress transmission and avoid collision or conversely to avoid excessive suppression of transmission is desirable.
For example, Patent Literature 1 discloses a technology for efficiently performing media access by temporarily changing a carrier sense level.